This code acts funky!

//scr 600*600
//====================================================================
#version 3.8;
global_settings {assumed_gamma 1 max_trace_level 20}
#include "colors.inc"
#default {finish{ambient 1 diffuse 0 emission 0}}

#background{rgb 1}
#declare Size=5;

camera{orthographic
        location <0,0,-Size>
        look_at <0,0,0>
        right Size
        up Size
        //sky y
        scale <1,1,1>
        }

sphere{-x*2,1 pigment{Red}}
sphere{0,1 pigment{Blue}}

scale the camera with <-1,1,1> and the Red sphere is where it should be
Does anyone else have this problem or is it just me?
I've got a 3Rd party build of PovRay v3.8.0 -beta.2+tgh7.msv14.win64

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Preview of image 'test.png'

On 10/18/26 19:35, Leroy wrote:
>          right Size
>          up Size

The right and up settings are vectors so 'Size' for both is getting 
promoted to <Size,Size,Size>.

My guess is that POV-Ray internally sees the identical promoted vectors 
as an invalid right/up vector combination and you end up with some 
parser de-mangled right/up vectors. I see no warnings that this is 
happening though, for which I'll give the parser ten demerits.

I think the de-mangling of the <Size,Size,Size> vectors might also be 
creating a sqrt(2) multiplier of the resulting, internal, right and up 
vectors. Or maybe this multiplier comes about otherwise - I don't know.

If I'm guessing well, using:

right <Size*sqrt(2),0,0>
up    <0,Size*sqrt(2),0>

would be valid right and up vectors where the orthographic camera scale 
will match what you are seeing currently for a confusing result - except 
now, with the red sphere showing up on the left as you expect.

Bill P.

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On 10/19/26 03:24, William F Pokorny wrote:
> If I'm guessing well, using:
> 
> right <Size*sqrt(2),0,0>
> up    <0,Size*sqrt(2),0>
> 
> would be valid right and up vectors...
Ugh, not quite correct - what I get for winging it. Those sqrt(2) 
multipliers should be sqrt(3) to match your original orthographic image 
scale.

Bill P.

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William F Pokorny <ano### [at] anonymousorg> wrote:
> On 10/19/26 03:24, William F Pokorny wrote:
> > If I'm guessing well, using:
> >
> > right <Size*sqrt(2),0,0>
> > up��� <0,Size*sqrt(2),0>
> >
> > would be valid right and up vectors...
> Ugh, not quite correct - what I get for winging it. Those sqrt(2)
> multipliers should be sqrt(3) to match your original orthographic image
> scale.
>
> Bill P.

I knew It was a simple problem. I just couldn't see it.

right x*Size
up y*Size

This does what I wanted.

It amazing that this worked at all.

right Size
up Size

And the strange way it acted with the x values inverted but not the y or z
values(I tested them) After I posted I tried the code on POV 3.7 win and it did
the same. So POV handles this problem the same way for a long time.

Thanks for your help!
Have Fun!

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